Parametric design is a process in which a few "outer" parameters (supplied by the design's end user) control the parameters set within the design. An algorithm is set up where the user is prompted for the outer parameters (such as new dimension values) or is otherwise asked to supply them. The computer then automatically designs the part after these values supplant the inner parameters (such as the variables labeling the master drawing). An electronic image of the part is stored in memory. And, this image can be used to produce either a drawing of the part (CAD) or to orchestrate the actual production of the part itself (computer-aided manufacturing, or CAM).
Heretofore available packages that offer parametric design capabilities to at least a limited extent include:
programming languages PA1 macros PA1 spreadsheet-format databases PA1 geometric rectification PA1 tabularized rectification PA1 nontabularized rectification PA1 spreadsheet rectification
Of these approaches, only the first three directly employ parametric design. The only comprehensive approach to computer aided parametric design heretofore available involves the use of a programming language to write a special purpose program which could do the design and output a drawing. The other methods lack sufficient power to establish a comprehensive design or are used in products that have a completely different objective and lend themselves to different goals. However, establishing a parametric design with a programming language is a laborious, time-consuming process that necessitates having the skills of a programmer.
As will become apparent hereinafter, applicants have invented a new and vastly improved method of generating parametric designs which involves a spreadsheet-driven rectification of a master drawing.
Rectification, by applicants' definition, is the subsequent modification that a drawing undergoes to conform with its new dimension text when the text is altered; it is a dimension-driven modification.
Tabularized and nontabularized rectification are used in some of the above-identified prior art approaches to the generation of parametric designs. The real purpose of tabularized rectification in the approaches is to save space within the computer. Spreadsheet rectification is used mainly for analysis. And, nontabularized rectification is used to enhance the editing process; it allows the user to insert a part as to position and angle, but it can only handle one part at a time.
The rectification capabilities listed above are in reality only editing tools and do not lend themselves to parametric design.